My soon-to-be ex-husband's ex fiance started working with me. I have no problem with her because I don't really know her, and what happened between the two of them is between them, in my opinion. However, she has been manipulating the manager and other co-workers to try to get me fired or to quit. I can't afford to just quit right now, not without another job lined up, and I don't want to cause someone else to lose a job just because there's a grievance. I've tried talking to her, and she says she doesn't have a problem with me, but it was through another co-worker that I learned she is going behind my back and trying to make it seem like I'm not doing my job properly and disrespecting customers. What can I do, besides quit?